McDonald's changed the recipe for its iconic Egg McMuffins -- here's how they're made

McDonald's changed the recipe for its iconic Egg McMuffins last year, and sales of the sandwiches exploded.

During a visit this week to McDonald's headquarters in Oak Brook, Illinois, the company's head chef, Jessica Foust, showed us how the popular breakfast sandwich is cooked and served today in restaurants across the country.

The ingredients that go into an Egg McMuffin include English muffins, eggs, butter, American cheese, and Canadian bacon.

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Foust emphasized that the American cheese is McDonald's own recipe and that it melts immediately when it hits a hot English muffin, creating a "sauce" for the entire sandwich.

McDonald's used liquid margarine on its breakfast sandwiches for many years, but last year switched to butter.

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"It just didn't taste as good," Foust said of the liquid margarine.

The swap was also made because customers were unfamiliar with liquid margarine, and they felt more comfortable with real butter, McDonald's executives said.

Sales of the Egg McMuffin grew by double digits following the switch, according to the company.

The first step in making McDonald's new-and-improved Egg McMuffin, as Foust demonstrates, is to toast the English muffins and melt several sticks of butter in a microwave for 30 seconds. Then the butter is mixed with a spoon for about one minute to create a "creamy sauce."

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When the butter comes out of the microwave, it should have a "chunky consistency," Foust said.

Once the mixture is smooth, it's poured into a plastic bottle using a funnel, and then squeezed over a toasted English muffin.

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Foust said the "nooks and crannies" in the English muffins provide some texture, "but really they are little pockets to hold melted cheese, butter, and all that flavor that you want in the sandwich."

To make sure McDonald's is getting the right portion of butter on every sandwich, employees make a "Ghostbuster symbol" with the melted butter — which is just a circle with a line through it.

"It allows us to deliver that consistent portion of butter on every sandwich," she said.

Meanwhile, the grill is heated up with McDonald's egg rings on top.

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The egg ring ensures that the uncooked egg doesn't run, and McDonald's has a consistent size and shape for its eggs.

Then butter is applied directly to the grill from a spray bottle.

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Every batch of eggs gets two squirts from the spray bottle.

Finally, it's time to crack some eggs.

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Like employees in McDonald's restaurants, Foust puts on gloves before handling the eggs, saying it's to reduce the chances of cross-contamination when handling raw eggs.

Foust said many people are surprised to learn that McDonald's cracks whole eggs onto the grill for its Egg McMuffins. Most people assume McDonald's uses liquid eggs, instead.

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The eggs are cracked onto the front of the grill, and then placed inside the rings.

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Before closing the grill, Foust breaks the yoke of every egg to make sure all the eggs cook at the same pace.

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Then she sprays water onto the eggs using this cylindrical device. The water allows the eggs to steam and poach in the ring, she says.

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The device is a special portioning tool designed for McDonald's that dispenses "just the right amount of water" onto the eggs.

The grill top is finally lowered on the eggs so they cook from both sides.

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The Canadian bacon, which is already cooked, is seared for extra flavor while the eggs continue to cook.

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After about two minutes on the grill, the eggs are done.

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They are scooped into a warming bin, and moved to a table for sandwich assembly.

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Finally, all the pieces are assembled together and the Egg McMuffin is ready to be served.